Bag making machine



April 14, 1936. sc 2,037,110

BAG MAKING MACHINE Filed June 9; 1933 .m INVENTOR. 1;?5

1% 3 ATrdRNEY.

Pmmd Apr. 14, 1936 UNITED STATES PATENT OFFICE A Application June 9, 1933, Serial No. 675,033 In Germany February 16, 1933 22 Claims. 93-27) 1 This invention relates primarily to machines for making flat or side fold bags and embodies more particularly a mechanism for closing or sealing the bottom of the bag. Bags are generally made by forming paper into tubes after which the tubes are cut to length and one end of each tube sealed to form a bottom closure for the bag.

The apparatus of this invention is constructed to receive a formed tube from any suitable forming apparatus to cut off the tube into the desired length with a flush cut end and to thereafter fold over the end of the tube and apply to the folded fiush cut end a pasted strip in a manner hereinafter more fully explained.

In the manufacture of closing the bottom of tubes to form bags of sensitive papers and transparent materials, such, for 'example, as transparent cellulose material, etc., considerable difl'lculty has been experienced in effecting the desired closure as these materials do not take an adhesive well and are not readily securely attached, particularly if the end of the tube is simply bent back upon itself and an attempt made to paste it in this condition. The sealing of tubes of transparent cellulose material and the like has constituted a diificulty in this art. The present invention overcomes these difficulties in a simple, eflicient manner and while adapted particularly for transparent cellulose material, it is not limited to this material exclusively, as it may be used with sensitive papers or other materials where a firm and tight bottom is desired economically on a flush out tube, i. e., a tube, the end of whichis cut off straight.

Speaking generally, the present invention embodies means, acting upon a web of material, to cut from said web a strip of appropriate size for application to one end of a tube to thereupon apply adhesive to the longitudinal marginal edges of the strip, to thereafter convey said strip into a position to apply one end thereof to one end portion of a tube, so fed as to meet and attach itself to one edge of the strip with an appreciable portion of the opposite edge of the strip 35 extending beyond the end of the tube. Means is further provided to thereupon crimp the end ofthe tube for the purpose of bending back the end portion of the tube and in this condition the thus crimped tube is fed to pressure means which completes the folding of the crimped portion and adhesively attaches the hitherto unattached end of the strip to the body of the tube above the fold.

The mechanism operates preferably in a continuous manner to permit tubes to be fed continuously through the machine with an automatic synchronization of the parts, whereby the strips are adhesively secured to the successive tubes and the tubes discharged from the machine in completed condition.

The invention while particularly directed to the apparatus for performing the operations stated also includes a method according to which these operations are performed.

Features of the invention, other thanthose adverted to, will be apparent from the hereinafter detailed description and claims, when read in conjunction with the accompanying drawing.

The accompanying drawing illustrates one practical embodiment of the invention, but the construction therein shown is to be understood as illustrative, only, and not as defining the limits of the invention.

Figure 1 is a diagrammatic showing of a machine embodying'the present invention.

Figure 2 is a plan view of a tube with one edge of the strip attached thereto and the tube crimped ready for final pasting down.

Figure 3 is a side elevation of the structure as shown in Figure 2.

Figure 4 is a face view of the finished tube.

Figure 5 is a side elevation thereof.

In the manufacture of bags, according to this til invention, the material from which the tubes are to be made is formed by suitable forming apparatus into tubular form and fed through a cutter indicated generally at i into engagement with feed rolls 2. The cutter periodically operates to cut off the tube at predetermined lengths and said tube, graphically illustrated at 3, is advanced between the feed rolls 2 to a point convenient for the application of the sealing strip.

The material from which the sealing strips are made is fed from a supply roll 4 about a guide roll 5 to and between feed rolls 6, which are driven at a uniform relatively low rate of speed. From these feed rolls, the web of paper I from the roll 4 passes over a tensioning roll-8 which functions somewhat after the manner of a looping roll, and from this roll the web 1 passes under a cut off roll 9, which rotates at a constant speed and in contact with the periphery of an operating cylinder I0.

The periphery of the'operating cylinder is provided with anannular recess l3 and in this recess runs an endless apron H which passes from neath the cutter roll 9 contacts for a distance with the apron II and then passes out of contact from the apron as the web is gripped between the rolls 9 and the cylinder Ill.

The cylinder I is provided at one point in its circumference with a longitudinal slot IS in which is adapted to operate a cutting blade I! carried by a plunger IS in the cutter roll 9. The rotation of the roll 9 and the cylinder I0 is timed so that periodically the cutter blade I! will aline with the slot I6 and at such times the cutter blade is adapted to be forced into the slot to cut the web interposed between said parts.

In practice, any appropriate means may be provided for synchronizing these operations, but I find it convenient for the purpose of illustration to show the plunger as operable by an impeller roll 20 carried on arms 2| pivoted at 22. A spring 23 normally tends to move the roll 20 into engagement with the roll 9, but a cam or eccentric 24 controls this engagement. chronized with the other parts of the machine, so that when the cutter blade I! approaches registration with the slots IS, the cam 24 lowers the roll 20 into contact with the roll 9 and as the roll 9 rotates, the end of the plunger I8 rides under the roll which forces the plunger downwardly and. drives the cutter knife through the paper. The plunger is normally spring retracted in any suitable manner, so that when the pressure of the roll 20 is relieved the plunger will be automatically retracted to withdraw the knife.

- The cutter roll 9 and the cylinder l0 are driven at higher speed than the drive rolls of the web and frictionally grip the web between them, so as to keep the web tight. Parts 9.and I0 may be driven at the same speed or difierent speeds as desired, the cam synchronizing the operations of the knife as stated.

The web is fed between roll 9 and cylinder l0 until its forward edge comes below grippers 25.

.Any number of these grippers may be provided,

the same being mounted on shaft 26 provided with an arcuate pinion 21 meshing with a rack 28 on a bell crank lever 29, the power arm of which carries a cam follower 30 cooperating with a cam 3| on the shaft 32 which carries the cylinder ID. A spring 33 tends to move the bell crank into a. position wherein the grippers 25 engage with and grip the forward end of the web as it is fed beneath said grippers,

The roll 9 has annular grooves therein, so that as the cylinder l0 rotates the grippers may pass through these grooves until they come into a position substantially as shown in the drawing. At this time, the web has been fed forwardly into a position wherein the grippers can descend and grasp the web 1, due to the shape of the cam 3| and while the forward end of the web is gripped, as stated, it is carried along by the grippers at the speed of rotation of the cylinder which is faster than the feed of the roll 6 and while this is occurring a cam 34 on shaft 35 permits the cam follower 36 to move to the left in Figure 1 carrying with it the arms 31 which support the lo'oping roll 8. This operation permits the web to straighten out between the feed roll 6 and the cutter roll 9 suiiiciently to preclude tearing of the web and after a sufficient portion of the forward part of the web has been fed to be equivalent to. the width of the strip desired, the knife I'I descends and cuts off said portion of the web to form a strip.

The strip thus formed is carried along by the grippers 25 and adhesive is applied to the leading The cam is syn-' sealed. The strip and the tube meet with the strip slightly in advance of the forward edge of the tube. The degree of advance is preferably equal to or slightly greater than the width of the glued portion at the forward marginof the strip. At about the time the strip meets and engages with the tube, the forward end of the tube is slightly in advance of dead center between shaft 32 and a shaft 42. The shaft 42 carries a reciprocating head 43 which is provided at one end with a crimping blade 44 and at the other end with a cam follower 45. The cam follower is adapted to cooperate with a cam or roll 46 normally retracted by a spring 41, but actuated by a cam 48 properly synchronized with the rest of the parts,

When the tube and strip meet as stated, the reciprocating head 43 is in a position so that the crimping blade 44 and a recess 49 in cylinder III are in substantial registration with a portion of the tube and strip between them. At this instant, the follower 45 passes beneath the roll 46 and this roll forces the head in an upward direction to force the crimping blade into the registering slot 49. Inasmuch as the tube and strip are interposed between these parts, the tube and strip are forced into slot 49 and crimped through this operation. It is desirable, however, that this crimp be in the form of a relatively tight fold, and consequently means is provided to pinch the fold while the tube and strip are in the slot 49. To this end, there is operable at one side of the slot, a movable jaw 50 pivoted on a shaft 5| to which is rigidly secured a lever 52 carrying a cam follower 53. This cam fol-' lower is controlled by a cam 54 rigid with shaft 3 2. Both cams 54 and 3| are stationary, while the cooperating parts revolve around them. A

spring 55 holds the cam follower in engagement with the cam 54. After the parts have been forced into the slot 49, the blade 44 immediately withdraws and as it is withdrawn the cam 54 permits the jaw 50 to grip and pinch the crimp thus formed in order to produce a tight fold. The grippers are meanwhile released to permit this operation to be efficiently carried out for the strip is by this time attached to the tube along one of its margins.

The operations thus far having been completed the parts appear as shown in Figs. 2 and 3 wherein the strip designated S is secured to the tube adhesively as indicated at 55. Both the tube and the strip are crimped as indicated at 51, while the adhesive margin 58 of the other end of the strip projects free.

The tube continues to move forward until its forward end engages a roll 59 carried on shaft 35 which roller deflects the tube upwardly and carries it between roll 59 and cylinder l 0 and the tube thereupon passes beneath the apron H and is carried along by the apron II and roll 59. However, as the tube passes between the roll 59 and the cylinder ID, the crimped end of the tube is folded down into the form shown in Figs. 4 and 5. The adhesive margin 58 being affixed to said strip into adhesive engagement with .the

the wall of the tube beyond the free edge of the returned end of the latter. Prior to passing out of the machine, it is furuther acted upon by a rotating presser 60 which applies a final pressure in the locality of the longitudinal margins of the strip to be sure that a tight adhesive. connection is made between the parts. Thereafter the tube is discharged from the machine between the rolls l5 and 59.

In the foregoing detailed description, I have described the machine as constructed so as to grippers 25 andtheir respective associated operating parts.

It will of course be understood that if the cylinder I0 is made of a larger size or it is desired to speed up production, these parts maybe duplicated a. plurality of times about the circumference of a cylinder, so that a plurality of strips will travel upon the cylinder at all times and .be formed and attached in succession. Furthermore, the web of paper is shown as introduced at the top of the machine and the tube at the bottom, these two elements meeting at the bottom and being applied at their lower part of the machine. The machine might, however, be built practically upside down, so that this relation of the parts might be reversed as will be readily understood in the art, depending upon conditions.

I have also described the rolls which operate the cutter knife and the crimping knife, as one being operated by a spring and the other by a cam. Either method of operation of these rolls may be employed or the cutting and crimping knives may be actuated by any other appropriate mechanism. The various parts of the machine are geared together or secured to one another by gears or sprocket chains, so as to synchronize all of the operations and to give a smooth running automatic machine as will be readily understood by those skilled in the art.

For-these reasons; the present invention is to be understood as not limited to specific details, but is to be construed as fully commensurate with the appended claims.

In the-drawing, the glue is applied to both edges of the strip at one time, but, if desired, one end of the strip can befirst glued and thereafter the other edge of the strip glued to the tube.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of making paper bags, which consists in applying adhesive to the marginal longitudinal edges of a strip-of material, thereupon adhesively securing one marginal edge of the strip transversely of an open ended tube with the other marginal edge of the strip projecting beyond the adjacent end of said tube, thereafter transversely crimping the tube beneath the strip; thereupon imparting pressure to the crimp thus formed to make a. tight fold, and thereafter further bending the thus folded portion of the tube and strip to bring the said projecting margin'of the strip in contact with the tube beyond the, re-

turned end thereof to adhesively secure said projectirig margin of the strip to the tube.

2. In an apparatus of the character described,

means for feeding an open ended tube along a predeterminedpath, means for applying an adhesive to one face of an elongated strip of ma.

terial, means for feeding the adhesive face of tube, the feeding means for the tube and the strip being such that the strip will be fed slightly in advance of the tube to secure the strip to the tube with a marginal portion of the strip projecting beyond the end of the tube, means acting upon the thus engaged tube and strip to bend the strip and juxtaposed portion of the tube along a line intermediate the longitudinal marginal edges of the strip, and means for thereafter forcing the projecting margin of the strip into adhesive engagement with the tube to seal the .end of the latter.

3. In an apparatus of the character described, means for feeding an open ended tube along a predetermined path, means for applying an adhesive to one face ofan elongated strip of material, meansfor feeding the adhesive face of said strip into adhesive engagement with the tube, the feeding means for the tube and the strip being such that the strip will be fed slightly in advance of the tube to secure the strip to the tube with a marginal portion of the strip projecting beyond the end of the tube, means acting upon the thus engaged tube and strip to crimp the strip and tube along a transverse line intermediate the longitudinal edges of the strip, and means for thereafter bending the tube on the line of crimping to bring portions of the tube on opposite sides of said line into face abutting engagement and to simultaneously fold the strip to bring the projecting portion thereof into adhesive engagement with the tube to seal the end of the latter.

4. In an apparatus of the character described, means for adhesively applying an elongated strip of material to one end of an open ended tube with one longitudinal margin of the strip ex; tending beyond the end of the tube, and means for thereafter returning said end of the tube upon itself and simultaneously adhesively applying the extending portion of the strip to the tube adjacent the returned end of the latter.

5. In an apparatus of the character described, means for adhesively applying an elongated strip of material to one endof an open ended tube with one longitudinal margin of the strip extending beyond the end of the tube, means for thereafter crimping the strip and juxtaposed portion of the tube transversely and on a line intermediate the longitudinal edges of the strip, and means for thereafter returning the said end of the tube upon itself by bending it along the line of the crimp and adhesively securing the extending end of the strip to the tube adjacent the returned end thereof.

6. In an apparatus of the character described, an operating cylinder, means for feeding a web of material tosaid cylinder, grippers associated with said cylinder to grip the forward end of the web, means for periodically cutting off predetermined lengths from the forward end of the web,

while the web is in engagement with the cylinder,

means for operating the grippers to grip the forward portion of the web prior to the cutting off of the latter to form a separate strip, means for applying an adhesive to the exposed face of the strip, means for feeding a tube into contact with each strip as the strip is carried by the cylinder to permit a strip tobe adhesively secured to each tube with the forward edge of thestrip projectcrimp thus formed to return the end of the tube '75 upon itself and adhesively secure the projecting end of the strip to the tube adjacent the returned end of the latter.

'7. In an apparatus of the character described, an operating cylinder, means for feeding a web of material to said cylinder, grippers associated with said cylinder to grip the forward end of the web, means for periodically cutting off predetermined lengths from the forward end of the web, while the web is in engagement with the cylinder, means for operating the grippers to grip the'forward portion of the web prior to the cut- .ting off of the latter to form a separate strip, means for applying an adhesive to the exposed face of the strip, means for feeding a tube into contact with each strip as the strip is carried by the cylinder to permit a strip to be adhesively secured to each tube with the forward edge of the strip projecting beyond the end of the tube, crimping means operable upon the tube and strip to crimp both of them simultaneously, while the strip is in engagement with the cylinder, said cylinder being provided with a re-entrant por-' tion, and said crimping means embodying a crimping blade with mechanism to force the blade into said re-entrant portion for the purpose of crimping the strip and tube, and means actin with the cylinder to thereafter bend said end of the tube back upon itself on the line of crimping and adhesively secure the projecting end of the strip to the tube adjacent the returned end of the latter. I

8. In an apparatus of the character described, a rotatable cylinder, means for positioning an elongated strip of material on said cylinder, means for holding the strip in engagement with the surface of the cylinder, means for applying adhesive to said strip, means for feeding a tube into engagement with the strip, as the latter travels with the cylinder to adhesively secure the strip to the end of the tube with the forward margin of the strip projecting beyond the end of the tube, said cylinder being provided therein with a re-entrant portion having an abutment, crimping means including a crimping blade with driving mechanism to drive the blade into the re-entra-nt portion to carry with it interposed portions, of the strip and tube for the purpose of crimping said portions, a movable jaw cooperating with said abutment and provided with operating means, operable in timed relation to the rotation of the cylinder, to press said portions of the tube and strip against said abutment to make a right fold in said portions, and means thereafter operable upon the tube and strip to force the projecting end of the strip into adhesive engagement with the tube.

9. In an apparatus of the character described,

an operating cylinder mounted ,to rotate and provided with periodically operating gripper jaws, means for feeding a web into engagement with the gripper jaws at a predetermined speed lower than the speed of the cylinder, a looping roll cooperating with said web to take up the slack therein and automatically compensate for differences in speed of the feed of the web and the rotation of the cylinder, means to periodically cut strips from the end of the web after said web has been gripped by the grippers, means to feed open ended tubes into engagement with the strip while the latter is held on the cylinder and to adhesively apply the strip to the tube with the forward end of the strip projecting beyond the end of the tube,- and means for thereafter returning the said end of the strip upon itself and adhesively securing the projecting portion of the strip to the tube adjacent the returned end portion of the latter.

10. In an apparatus of the character described, means for adhesively applying a strip of material to one side of an open ended tube with one lateral margin of the strip projecting beyond the end of the tube, means for thereafter folding over the end portion of the tube together with the overlying portion of the strip to close the end of the tube, and means for pressing said projecting margin of the strip into adhesive engagement with the opposite side of the tube.

11. In an apparatus of the character described, the combination of feeding devices for feeding a strip of material and a tube, at least one of which is gummed, into engagement with one another at a predetermined point with the strip fed in advance of the tube for the purpose of adhesively securing the tube and strip in face abutting relation with one end of the strip projecting beyond the corresponding end of the tube, and means for folding over said end of the tube and the overlying portion of the strip to bring the projecting portion of the strip into adhesive engagement with the opposite side of the tube.

12. In a bag making machine, the combination of means for feeding an unfolded, open ended tube and a strip into face abutting, overlapping relation, means for folding over the end of the tube to close the same and for folding over the strip to overlie the folded end of the tube, and mechanism to apply extrinsic securing means for securing the folded portions of the tube and strip in such folded condition. 7

13. In an apparatus of the character described, a rotary operating cylinder, grippers associated with said cylinder to grip and hold a strip on said cylinder, means for applying an adhesive to the exposed face of the strip, means for feeding a tube into contact with the strip, as the strip is carried by the cylinder, to permit the strip to be adhesively secured to the tube with the one end of the strip projecting beyond one end of the tube, means for thereafter crimping the tube transversely at a distance from said end to facilitate folding thereof, and means for folding over the end of the tube and strip at the crimp thus formed to return the end of thetube upon itself and adhesively secure the projecting end of the strip to the opposite side of the tube adjacent the returned end of the latter. 14. In an apparatus of the character described, a rotary operating cylinder, means for feeding a web of material at a predetermined speed different from the speed of rotation of the operating cylinder, a looping roll cooperating with the web to compensate for said differences in speed, means to periodically cut strips of predetermined length from the forward end of said web, grippers to engage with and hold each strip on the cylinder, means to feed an open ended tube into engagement with each strip while the latter is held on the cylinder and to adhesively apply the strip to the tube with the forward end of the strip projecting beyond the end of the tube, and means for thereafter returning the said end of the tube upon itself and adhesively securing 'the'projecting portion of the strip to the tube adjacent the returned end portion of the latter.

15. In an apparatus of the character described, I

an operating cylinder provided therein with a re- .entrant portion, grippers associated with the cylinder'to grip and carry alonga strip of ma terial, means for applying an adhesive to the of the tube upon itself and adhesively secure the projecting end of the strip to the opposite side of the tube adjacent the returned end of the latter.

16. The method of making bags which consists in causing an open ended tube and a strip of material to travel along predetermined paths to a point of meeting, applying an adhesive to the strip prior to its arrival at said meeting point, and at said meeting point adhesively securing, while the tube and strip continue to travel, one lateral portion of the strip to one side of the tube with the other lateral portion of the strip projecting beyond one end of the tube and with the opposite side of the tube wholly unencumbered by the strip, thereafter folding over said end of the tube together with the strip to close the end of the tube and adhesively securing the projecting portion of the strip in face abutting relation to said opposite side of the tube.

17. The method of making bags'which consists in causing an open ended tube and a strip of material to travel along predetermined converging paths to a point of meeting with the strip fed slightly in advance of the tube to cause them to meet in face abutting relation at said point with one lateral portion of the strip in face abutting relation with one side of the tube, and the other lateral portion of the strip projecting beyond the end of the tube and with the opposite side of the tube wholly unencumbered by the strip, adhesively securing the tube to that lateral portion of the strip which is in face abutting relation thereto, thereafter folding over the end portion of the tube to close said end of the tubetand bring said projecting portion of the strip into face abutting relation with said opposite side of the tube and beyond the returned end portion of the latter,

and adhesively securing said projecting end p ortion of the strip to the tube.

18. In a machine for closing the front edges of smoothly cut tubular bag blanks, a paper band supply roller, feeding rollers for continuously feeding paper from the said supply roller device, a cutting device for periodically severing strips from the front edge of the said band, a pair of cooperating cylinders comprising means for gripping, forwarding and folding the said severed strips, a means for applying two strips of gluing material parallel and near to the front .end and rear edge of the said severed strips, means to deliver to the gripping line of the said folding cylinders the front ends of the'cut pieces of the paper tube in such a manner as to have the said severed pieces glued on to the front edge of each delivered tubular bag blank in a predetermined position, a pressing drum cooperating" with the upper of the said pair of folding cylinders so as to sharply fold the said severedpiece when placed over the front edge of the said blank at the fold= ing line created by the said folding means, and a guiding narrow ribbon passed over the upper folding cylinder and the said pressing drum and accompanying the said severed piece from its way from the cutting device towards the delivery point of the machine.

19. In a machine for forming a bottom closure on a tubular bag blank the combination of means for continuously feeding a paper band, means for periodically severing transverse strips from the front edge of said band, means for forwarding such severed strips comprising pping means engaging their front edges, means for applying adhesive material to said strips during said forwarding movement and crosswise thereof close to their front and rear edges so as to form paste strips, means for feeding a series of bag blanks toward said strip-forwarding means so timed .and arranged relatively thereto that the rear paste stripes of successive severed strips will be applied to successive bag blanks with the front edge of each of the latter situated between the two said paste stripes but closer to the front one, folding means acting upon such assembled strips and bag blanks at substantially the middle of the former and between said paste stripes, and means for pressing the paste-bearing front edge portions of each strip against its associated bag blank; whereby the paste bearing edge portions of each strip are caused to adhere to op- 'posite, surfaces of said bag blank and thereby close one end thereof to form the completed bag.

20. In a bag-forming machine comprisng mechanism for feeding a tubular bag blank e'ndwise thereto, the combination, with said mechanism, of means for also feeding a web of flexible material thereto, means for cutting said web transversely to form a relatively narrow strip, means for applying still narrower stripes of paste along one surface of said strip adjacent each edge thereof, mechanism for applying one only of such paste-bearing edge portions to one end of said bag blank and for folding the other around said blank end, and means for pressing the other paste-bearing edge portion of said strip against the other face of said blank; whereby that end of said blank is closed to form a completed bag.

21. A combination such as defined in the preceding claim in which said folding mechanism is adapted to also engage and fold-over the extreme end portion of said blank within said folded strip.

22. In a machine for closing the front edges of smoothly cut tubular bag blanks,the combination of means for supporting a roll of flexible material, feeding rollers for continuously feeding said web of material therefrom, a .knife for periodically severing transversestrips from the front end portion of said web, a camactuated guiding and tension roller for controlling the movement of the web section extending from said folding tongs in the said upper cylinder comprising one jaw fixed relatively to the said cylinder and a second jaw arranged for oscillatory movement with respect to said first jaw, the said jaws forming a folding groove between them parallel to the axis of said cylinder and so arranged-- with respect to-said gripping means that said groove underlies the middle of said severed piece while it is gripped by said gripping means, a foldproducing blade mounted in the said lower cylinder so as to slide radially thereof, means for momentarily pushing upward the said blade toward the said folding groove whenever one of said strips is passing the gripping line between saidfolding cylinders, means for oscillating said oscillatory jaw towards its said cooperating jaw just after the folding operation has been completed, a cutting device for periodically cutting pieces from the front end of a continuously advanced paper tube, means for forwarding said out pieces toward the gripping line between said folding cylinders so timed with respect to the upper cylinder that the rearward paste strip on each of said first mentioned severed strips is placed on the upper surface of said tube piece, while the'front paste strip lies in front of the forward edge of the latter just before the gripping line is reached, means for releasing the said gripping means after said severed strip and tube piece have been pasted together, and means for folding over the front portion of the said two pasted pieces after they have passed the gripping line.

LUDWIG BISCHOFF. 

